Crushing analysis and design optimization for foam-filled aluminum/CFRP hybrid tube against transverse impact

Abstract

Aluminum foam, carbon fiber reinforced plastics (CFRP) and foam-filled structures have been drawn growing attention for their outstanding lightweight and energy absorption capacity; therefore, crushing characteristics of a hybrid system involving these components would be of particular interest. In this study, quasi-static compression tests were carried out to experimentally investigate the crushing behaviors of foam-filled aluminum/CFRP hybrid tube subject to transverse loading condition. Based upon the experimental tests and numerical modeling, the interactive effects in between the aluminum foam filler and aluminum/CFRP hybrid tube was explored. It is found that the load carrying and energy absorption capacities of foam-filled hybrid tube were significantly improved in comparison with the summation of net foam filler and empty hybrid tube. The parametric study was carried out for exploring the effects of the aluminum foam density, aluminum tube thickness and ply number of CFRP tube on the crushing behaviors of foam-filled hybrid tube. It is found that both the total energy absorption (EA) of foam-filled hybrid tubes and the EA contributions of the aluminum foam (or aluminum tube, or CFRP tube) were enhanced with increase in density (or thickness, or ply number). The specific energy absorption (SEA) of foam-filled hybrid tubes increased from 3.45 J/g to 9.24 J/g with the foam density changed from 0.23 g cm−3 to 0.70 g cm−3; nevertheless, increase in aluminum tube thickness (or ply number of CFRP tube) has no evident influence on the SEA of foam-filled hybrid tubes. Finally, discrete design optimization was further performed to obtain the best possible foam-filled hybrid configuration for the transverse crushing characteristics. The optimum results showed that the SEA was largely improved by 213% in comparison with the baseline design.